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Fatigue cracking is a major distress in asphalt concrete and has a significant influence on material performance. A coupled extended finite element method (XFEM)-continuum damage mechanics ...

The rejuvenator is typically utilized to partially recover the mechanical properties of reclaimed-asphalt pavement (RAP). Although the rejuvenator works effectively in softening the highly ...

Dynamic shear modulus of an asphalt mastic has a remarkable effect on the mechanical performance of an asphalt pavement, and particulate composite micromechanical models are proven to be su...

This article presents a method of geopolymerizing black cotton soil (BCS), a type of highly expansive soil, to ascertain its potential use in subgrades. The BCS is stabilized by alkalis of ...

This study focused on the property characterization of asphalt and asphalt mixtures modified by different types of crumb rubber (normal and desulfurized). This characterization was based on...

It has been observed that permanent deformation (or rut) in the asphalt pavement at an intersection is much more severe than a deformation away from the intersection due to breaking horizontal forces and longer loading time. This paper presents both experimental and numerical investigations of this phenomenon, and the numerical investigations are validated by three-dimensional fiber-reinforced polymer-optical fiber Bragg grating sensors. First, a field investigation of the rutting at four signalized intersections in Nanjing (Jiangsu, China) leads to the conclusion that under braking traffic and static loads, the values of voids in the mineral aggregate (VMA) and air-void content could be less than the minimum desirable values. Second, the permanent deformations associated with tangential and vertical forces and their loading time assessed with the finite-element method are compared with those measured from instrumentations. This analysis demonstrates that hot-mix asphalt pavement at the intersections should maintain adequate VMA to ensure durability, and a minimum desirable percentage of air voids under slow and standing traffic loads during hot summer days. The permanent deformations at the intersections caused by tangential and vertical forces are both serious and need to be restricted. It is also shown that the permanent deformation is sensitive to both the traffic load and its loading time, but the sensitivity of the load is more pronounced.

Recently, a shape memory polymer-based self-healing syntactic foam was proposed and tested as a sealant for expansion joints. The key for success is to train the foam by using a two-dimensional (2D) stress condition (compression in the horizontal or traffic direction and tension in the vertical direction) at a temperature above the glass transition temperature (Tg). However, for practical applications, programming a full-size slab of sealant with a 2D stress condition and under temperature control is not a trivial task. This study demonstrated that the programming with a one-stage 2D stress condition can be replaced by a sequential two-stage one-dimensional (1D) stress condition. To further simplify the programming process, 1D tension programming was conducted at a temperature above the Tg, followed by 1D compression programming at a temperature below the Tg (cold compression). The test results show that the hybrid programming leads to similar shape memory behavior as long as the prestrain level i...

Open graded friction course (OGFC) is effective in improving the surface function of asphalt pavements. However, it is prone to clogging including deformation-related and particle-related clogging. The aim of the research reported in this paper is to investigate the permeability loss or reduction due to deformation-related clogging and explore the critical size of solid particles attributed to OGFC particle-related clogging. A special falling head permeameter was developed with consideration of both rainwater flowing procedure and the pavement transversal slope. Eight types of OGFC mixtures with different air void contents, gradations, and nominal maximum aggregate sizes were prepared for deformation-related clogging evaluation. Wheel rutting tests were conducted on the OGFC samples with different loading times under two load levels [(1) 700 kPa, and (2) 900 kPa] at 45 and 60°C, and next were permeability tests using the developed permeameter. Permeability loss after different wheel loading times ...